A survey was performed to (1) assess the rate of vehicle emission tampering on a nationwide basis, (2) assess the most prevalent forms of tampering, and (3) quantify the relationship between tampering and idle test emission scores. 1953 vehicles comprising model years 1973 through 1978 were inspected in Delaware, Maine, Virginia, Washington, Tennessee, and Texas, during state safety inspections or police roadside checks. An overall tampering rate of 5.8% was found. Tampering increased with age of the vehicle and, in general tampered vehicles had higher idle emissions. Tampering was most prevalent with the exhaust gas recirculation system.
Motor Vehicle Tampering Survey (1978)
1978
113 pages
Report
No indication
English